Increased solubilization of iscotrizinol

ABSTRACT

The present invention relates to cosmetic composition comprising an ester of a fatty acid and dextrin, a mixture of branched and linear saturated C15-C19, wherein said mixture comprised primarily branched saturated C15-C19, and a UV-filter of the formula (I). This cosmetic composition allows a high amount of the UV-filter of the formula (I) to be solubilized which leads to compositions having a very high absorbance of harmful UV light, i.e. to compositions having a high Sun Protection Factor (SPF).

TECHNICAL FIELD

The present invention relates to the field of cosmetic compositionswhich protect from UV light, particularly to cosmetic compositionscomprising the UV-filter Iscotrizinol.

BACKGROUND OF THE INVENTION

Iscotrizinol is an highly effective UV(B) filter with an exceptionalhigh absorptivity of the harmful UV light and is broadly used incosmetic compositions. It has an outstanding photostability and moderatesolubility particularly in esters and alcohols. However, the solubilityin water and alkanes is very low.

It is important for the acceptance of a cosmetic composition that it hasgood sensory properties. Particularly the skin feeling is important.Products which result in a silky or velvet skin feeling on touch orfresh and gliding sensation with soft finish or comfortably afterfeelare significantly better accepted in the market.

Traditionally, silicone oils are used to improve the sensory propertiesin this direction. As the use of silicones oils in cosmetic products aregetting more and more under pressure in the market particular forenvironmental and regulatory reasons, alternative substances leading toan increase of the sensory properties are highly searched.

It has been found that liquid C8-C30 alkanes can be used to improve thesensory properties and are suggested to be used for replacing siliconeoils.

For example WO 2018/109353 A1 discloses a mixture of branched and linearsaturated C15-C19 alkanes to improve the sensory properties of anoil-in-water emulsion.

A partial replacement of the solvent in cosmetic composition by suchliquid alkanes with the goal to achieve improved sensory properties,however, reduces significantly the solubility of the UV filterIscotrizinol, and, hence, leads to a strong reduction of the sunprotection factor (SPF) of a respective cosmetic composition.

SUMMARY OF THE INVENTION

Therefore, the problem to be solved by the present invention is toobtain a high solubilization of the UV filter Iscotrizinol comprisingliquid C8-C30 alkanes, particularly C15-C19 alkanes, in cosmeticcompositions which have in particular improved sensory properties.

Surprisingly, it has been found that the cosmetic composition accordingto claim 1 allows to solve this problem.

It has been particularly found that this solution represent a highlysustainable and advantageous approach for this problem, as esters offatty acids can be obtained from biological resources. This solution iseven more attractive as also the preferred mixtures of C15-C19 alkanescan be obtained from biological origin. It is therefore, possible tooffer cosmetic compositions having high sun protection factor (SPF) aswell as excellent sensory properties.

Further aspects of the invention are subject of further independentclaims. Particularly preferred embodiments are subject of dependentclaims.

DETAILED DESCRIPTION OF THE INVENTION

In a first aspect the present invention relates to a cosmeticcomposition comprising

-   -   an ester of a fatty acid and dextrin    -   a mixture of branched and linear saturated C15-C19 alkanes    -   a UV-filter of the formula (I)

-   -   wherein the amount of branched saturated C15-C19 alkane in said        mixture of branched and linear saturated C15-C19 alkanes is more        than 80% by weight, preferably more that 90% by weight, most        preferred more than 92% by weight.

For sake of clarity, some terms used in the present document are definedas follows:

In the present document, a “C_(x)-C_(y) alkane” is an alkane comprisingx to y carbon atoms, i.e., for example, a C15-C19 alkane is an alkanecomprising 15 to 19 carbon atoms. The alkane can be linear or branched(i.e. non-linear) and are purely saturated hydrocarbons. For example,all alkanes having the molecular formula C₁₅H₃₂, C₁₆H₃₄, C₁₇H₃₆, C₁₈H₃₈and C₁₉H₄₀, such as pentadecane, octadecane, nonadecane,2,6,10,14-tetramethylpentadecane, isohexadecane, are regarded as C15-C19alkanes. Particularly preferred branched alkanes are branched alkaneshaving exclusively methyl group(s) as side chain(s), such as e.g.2,6,10,14-tetramethylpentadecane, 2-methylpentadecane or3-methylpentadecane.

In case identical labels for symbols or groups are present in severalformulae, in the present document, the definition of said group orsymbol made in the context of one specific formula applies also to otherformulae which comprises the same said label.

The term “UV filter” in the present document stands for a substance thatabsorbs ultraviolet light (=UV light), i.e. electromagnetic radiation ofthe wavelength between 280 and 400 nm.

A liquid organic UV filter is liquid at ambient temperature (i.e. 25°C.).

A solid organic UV filter is solid at ambient temperature (i.e. 25° C.).

The term “solubilize” or “solubilization” in the present documentdescribes the property that the UV filter of the formula (I) isincorporated in the cosmetic composition in such a manner that theUV-filter is not precipitated or separated at ambient temperature fromthe composition.

A “mixture of branched and linear saturated C15-C19 alkanes” in thepresent document means that said mixture comprises different alkaneseach of them only having 15, 16, 17, 18 or 19 carbon atoms but does notcomprise any alkanes having less carbons. Therefore, such a mixture doesnot contain for example dodecane or isododecane. Said mixture comprisesboth branched and linear C15-C19 alkanes.

UV Filter of Formula (I)

The cosmetic composition comprises the UV-filter of the formula (I)

The UV-filter of the formula (I) (CAS: [154702-15-5]) is a light yellowcrystalline solid with a melting point of 52-55° C. and is also known asIscotrizinol or diethylhexyl butamido triazone (INCI). The UV filter isa highly effective UV(A) and UV(B) filter with an exceptional highabsorptivity and is very highly photostable.

It has an absorption maximum of about 310 nm. It is commerciallyavailable for example under the trademark UVASORB® HEB from 3V Sigma.

Due to its polarity, it is very soluble in esters, and alcohols,particularly in ethanol, however, is insoluble in water and alkanes.

Ester of a Fatty Acid and Dextrin

The cosmetic composition further comprises an ester of a fatty acid anddextrin.

Dextrin is an oligomer polymers of D-glucose. Its structure can berepresented simplified by the following structure

Dextrins have different average degrees of glycopolymerization whichleads to different molecular weights.

In the present invention, the dextrin of said ester of a fatty acid anddextrin has preferably an average degree of glycopolymerization ofbetween 3 and 20, particularly between 8 and 16.

It is preferred that the fatty acid of said ester of a fatty acid anddextrin is a C14-C18 fatty acid, particularly a linear C14-C18 fattyacid, most preferably palmitic acid.

As particular suitable ester of a fatty acid and dextrin is a dextrinpalmitate as commercialized as Rheopearl® KL2 by Chiba Flour Milling.

Dextrin has several hydroxyl groups which can be esterified.

It is preferred that said ester of a fatty acid and dextrin has anaverage number of esterified hydroxyl groups of more than 2.5,preferably between 2.7 and 3.5, more preferably between 28 and 3.4, mostpreferably between 2.8 and 3.2, per glucose unit.

In one embodiment said ester of a fatty acid and dextrin has an averagenumber of esterified hydroxyl groups of more than 3, preferably between3.05 and 3.5, more preferably between 3.1 and 3.4, most preferablybetween 3.1 and 3.2, per glucose unit.

In other words, preferably essentially all of the hydroxyl groups of thedextrin are esterified.

It is further preferred that said ester of a fatty acid and dextrin hasan molecular weight M_(n) of between 8,000 and 16,000 Da, preferablybetween 9,000 and 13,000 Da, more preferably between 10,000 and 11′500Da.

The molecular weight M_(n) is determined in Dalton (Da) particularly bySEC/GPC using polystyrene as standard.

Both fatty acid and dextrin have biological origin. The biologicalorigin of chemicals is very advantageous as such material or productsthereof have a high degree of sustainability. High sustainable productsor compositions are highly demanded in the market.

Mixture of Branched and Linear Saturated C15-C19 Alkanes

The cosmetic composition comprises a mixture of branched and linearsaturated C15-C19 alkanes.

Particular suitable mixtures of C15-C19 alkanes are particularly theones disclosed in WO 2016/185046, WO 2017/046177, WO 2018/109353 A1 andWO 2018/109354 A1 and WO 2018/172228 A1.

Preferably, the mixture of branched and linear saturated C15-C19 alkaneshas a content of carbon of biological origin being greater or equal to90% with respect of the total weight of the mixture of branched andlinear saturated C15-C19 alkanes. The biological origin of chemicals isvery advantageous as such material has a high degree of sustainability.High sustainable products or compositions are highly demanded in themarket.

The determination of the content of biomaterial or content of biocarbonis given pursuant to standards ASTM D 6866-12, method B (ASTM D 6866-06)and ASTM D 7026 (ASTM D 7 026-04). Standard ASTM D 6866 concerns“Determining the Biobased Content of Natural Range Materials UsingRadiocarbon and Isotope Ratio Mass Spectrometry Analysis”, whilestandard ASTM D 7 026 concerns “Sampling and Reporting of Results forDetermination of Biobased Content of Materials via Carbon IsotopeAnalysis”. The second standard mentions the first in its firstparagraph. The first standard describes a test of measurement of theratio ¹⁴C/¹²C of a sample and compares it with the ratio ¹⁴C/¹²C of asample renewable reference of origin 100%, to give a relative percentageof C of origin renewable in the sample. The standard is based on thesame concepts that the dating with ¹⁴C.

It is further preferred that the composition has no or a very smallamount (less than 100 ppm, particularly less than 30 ppm) of aromatichydrocarbons with respect to the total weight of the mixture of branchedand linear saturated C15-C19 alkanes.

The mixture of branched and linear saturated C15-C19 alkanes isparticularly produced by catalytic hydrogenation of hydrocarbon biomassfeedstock, such as described in detail in WO 2016/185046, particular theone disclosed as example 3 of WO 2016/185046.

It is preferred that the amount of linear saturated C15-C19 alkanes insaid mixture of branched and linear saturated C15-C19 alkanes is lessthan 10% by weight, preferably less than 8% by weight, most preferredmore than 5% by weight.

It is further preferred that the amount of C15 is less than 3%,particularly less than 1%, preferably less than 0.05%, by weight inrespect to the weight of said mixture of branched and linear saturatedC15-C19 alkanes.

It is preferred that the mixture of branched and linear saturatedC15-C19 alkanes is a mixture of branched and linear saturated C16-C19alkanes.

It is further preferred that the amount of branched saturated C16-C18alkane is more than 90% by weight, preferably more than 95% by weight inrespect to the weight of said mixture of branched and linear saturatedC15-C19 alkanes.

It is further preferred that the amount of C15 alkanes is less than 5%,particularly less than 2%, by weight in respect to the weight of saidmixture of branched and linear saturated C15-C19 alkanes.

It is further preferred that the amount of branched saturated C17-C18alkane is more than 85% by weight, preferably more than 92% by weight inrespect to the weight of said mixture of branched and linear saturatedC15-C19 alkanes.

It is further preferred that the amount of C17 alkanes is more between15 and 20% by weight in respect to the weight of said mixture ofbranched and linear saturated C15-C19 alkanes.

It is further preferred that amount of branched saturated C18 alkane ismore than 50% by weight, preferably more than 60% by weight, even morepreferably more than 70% by weight, relative to the weight of saidmixture of branched and linear saturated C15-C19 alkanes.

It is further preferred that the amount of C18 alkanes is particularlybetween 70 and 75% by weight in respect to the weight of said mixture ofbranched and linear saturated C15-C19 alkanes.

In other words, the mixture of branched and linear saturated C15-C19alkanes consist preferably mainly of C18 alkane(s), most preferablymainly of branched C18 alkane(s).

As the cosmetic composition comprises a mixture of branched and linearsaturated C15-C19 alkanes, said composition does not comprise any loweralkanes, i.e. it does particularly not comprise any C12 alkanes andparticularly does not comprise any C12 or C13 or C14 alkanes.

It is further preferred that the mixture of C15-C19 alkanes has at 20°C., a viscosity of 3-15 mPas, particularly between 6 and 12 mPas.

It is further preferred that the mixture of C15-C19 alkanes has at 20°C. a refractive index of between 1.40 and 1.48, particularly of between1.42 and 1.45, most preferably between 1.43 and 1.44.

It is further preferred that the mixture of C15-C19 alkanes is themixtures of C15-C19 alkanes as commercialized as EMOGREEN™ L19 bySEPPIC.

In the said composition the ratio of the weight of said ester of a fattyacid and dextrin to the weight of said mixture of branched and linearsaturated C15-C19 alkanes is preferably less than 100% by weight,preferably in the range of 50-80% by weight, most preferred in the rangeof 60-70% by weight.

In other words, the composition comprises preferably more, by weight, ofthe C15-C19 alkanes than of the ester of a fatty acid and dextrin.

Furthermore, in said composition the weight ratio of the UV-filter ofthe formula (I) to the ester of a fatty acid and dextrin is preferablyis 100:1 to 1:100, preferably 80:1 to 1:100, more preferably 70:1 to1:20, most preferably 60:1 to 1:10.

Furthermore, it is preferred that said composition is in the form of agel.

It is preferred that the cosmetic composition has a viscosity, measuredon a Rheometer AR550 from TA Instruments using a 40 mm plate and a shear10/s at 25° C., of more than 1,000 mPas, preferably more than 2,000 mPas. It is further preferred that said viscosity is less than 100,000mPas, preferably less than 50,000 mPas, more preferred less than 40,000mPas.

Said composition has preferably a Sun Protection Factor (SPF) of 10 orhigher, preferably of 20 or higher, more preferred of 30 or higher, evenmore preferred 50 or higher.

It is preferred that the mixture of branched and linear saturatedC15-C19 alkanes and the a fatty acid and dextrin are both based onorganic origin.

It is furthermore preferred that the mixture of branched and linearsaturated C15-C19 alkanes and the ester of a fatty acid and dextrin arereadily biodegradable according to OECD 301B.

The cosmetic composition may comprise also further organic or inorganicUV filters known to the person skilled in the art of cosmetics and sunprotection.

The cosmetic composition typically comprises other ingredients which aresuitable for the use in cosmetic compositions.

The cosmetic composition comprises preferably water.

The cosmetic compositions preferably may be in the form of a suspensionor dispersion in solvents or fatty substances, or alternatively in theform of an emulsion or micro emulsion (in particular of oil-in-water(O/W-) or water-in-oil (W/O-)type, silicone-in-water (Si/W-) orwater-in-silicone (W/Si-)type, PIT-emulsion, multiple emulsion (e.g.oil-in-water-in oil (O/W/O-) or water-in-oil-in-water (W/O/W-)type),pickering emulsion, hydrogel, alcoholic gel, lipogel, one- or multiphasesolution or vesicular dispersion or other usual forms, which can also beapplied by pens, as masks or as sprays.

Preferred cosmetic compositions in all embodiments of the presentinvention comprise water and are in the form of an emulsion.

The emulsion particularly contain an oily phase and an aqueous phasesuch as in particular O/W, W/O, Si/W, W/Si, O/W/O, W/O/W multiple or apickering emulsions.

The total amount of the oily phase present in such emulsions ispreferably at least 10 wt.-%, such as in the range from 10 to 60 wt.-%,preferably in the range from 15 to 50 wt.-%, most preferably in therange from 15 to 40 wt.-%, based on the total weight of the cosmeticcomposition.

The amount of the aqueous phase present in such emulsions is preferablyat least 20 wt. %, such as in the range from 40 to 90 wt.-%, preferablyin the range from 50 to 85 wt.-%, most preferably in the range from 60to 85 wt.-%, based on the total weight of the cosmetic composition.

More preferably, the cosmetic compositions are in the form of anoil-in-water (O/W) emulsion comprising an oily phase dispersed in anaqueous phase in the presence of an O/W- respectively Si/W-emulsifier.The preparation of such emulsions is well known to a person skilled inthe art.

The compositions in form of O/W emulsions can be provided, for example,in all the formulation forms for O/W emulsions, for example in the formof serum, milk or cream, and they are prepared according to the usualmethods. The compositions are preferably intended for topicalapplication and can in particular constitute a dermatological orcosmetic composition, for example intended for protecting human skinagainst the adverse effects of UV radiation (antiwrinkle, anti-ageing,moisturizing, sun protection and the like).

The cosmetic composition further preferably comprises at least oneemulsifier, preferably an anionic emulsifier. Preferably the anionicemulsifier is an anionic emulsifier selected from the group consistingof potassium cetyl phosphate, disodium cetearyl sulfosuccinate, sodiumstearoyl glutamate, sodium stearoyl lactylate, glyceryl stearate citrateand sodium cocoyl isethionate.

In one advantageous embodiment, the cosmetic compositions in additioncontain a phosphate ester emulsifier. Among the preferred phosphateester emulsifier are C8-10 Alkyl Ethyl Phosphate, C9-15 Alkyl Phosphate,Ceteareth-2 Phosphate, Ceteareth-5 Phosphate, Ceteth-8 Phosphate,Ceteth-10 Phosphate, Cetyl Phosphate, C6-10 Pareth-4 Phosphate, C12-15Pareth-2 Phosphate, C12-Pareth-3 Phosphate, DEA-Ceteareth-2 Phosphate,DEA-Cetyl Phosphate, DEA-Oleth-3 Phosphate, Potassium cetyl phosphate,Deceth-4 Phosphate, Deceth-6 Phosphate and Trilaureth-4 Phosphate. Aparticular phosphate ester emulsifier is potassium cetyl phosphate e.g.commercially available as Amphisol® K at DSM Nutritional Products LtdKaiseraugst.

The cosmetic composition can also comprise nonionic emulsifiers.

Examples of nonionic emulsifier include condensation products ofaliphatic (C8-C18) primary or secondary linear or branched chainalcohols with alkylene oxides, usually ethylene oxide and generallyhaving from 6 to 30 ethylene oxide groups. Other representative nonionicemulsifiers include mono- or di-alkyl alkanolam ides such as e.g. cocomono- or di-ethanolamide and coco mono-iso-propanolamide. Furthernonionic emulsifiers which can be included are the alkyl polyglycosides(APGs). Typically, the APG is one which comprises an alkyl groupconnected (optionally via a bridging group) to a block of one or moreglycosyl groups such as e.g. Oramix™ NS 10 ex Seppic; PLANTACARE® 818UP,PLANTACARE® 1200 and PLANTACARE® 2000 ex BASF.

If the cosmetic composition is an O/W emulsion, then it preferablycontains at least one O/W- or Si/W-emulsifier selected from the list ofPEG-30 Dipolyhydroxystearate, PEG-4 Dilaurate, PEG-8 Dioleate, PEG-40Sorbitan Peroleate, PEG-7 Glyceryl Cocoate, PEG-20 Almond Glycerides,PEG-25 Hydrogenated Castor Oil, Glyceryl Stearate (and) PEG-100Stearate, PEG-7 Olivate, PEG-8 Oleate, PEG-8 Laurate, PEG-60 AlmondGlycerides, PEG-20 Methyl Glucose Sesquistearate, PEG-40 Stearate,PEG-100 Stearate, PEG-80 Sorbitan Laurate, Steareth-2, Steareth-12,Oleth-2, Ceteth-2, Laureth-4, Oleth-10, Oleth-10/Polyoxyl 10 OleylEther, Ceteth-10, Isosteareth-20, Ceteareth-20, Oleth-20, Steareth-20,Steareth-21, Ceteth-20, Isoceteth-20, Laureth-23, Steareth-100,glycerylstearatcitrate, glycerylstearate (self-emulsifying), stearicacid, salts of stearic acid, polyglyceryl-3-methylglycosedistearate.Further suitable emulsifiers are sorbitan oleate, sorbitan sesquioleate,sorbitan isostearate, sorbitan trioleate, Lauryl Glucoside, DecylGlucoside, Sodium Stearoyl Glutamate, Sucrose Polystearate and HydratedPolyisobuten.

Furthermore, one or more synthetic polymers may be used as anemulsifier. For example, PVP eicosene copolymer, acrylates/C10-30 alkylacrylate crosspolymer, acrylates/steareth-20 methacrylate copolymer,PEG-22/dodecyl glycol copolymer, PEG-45/dodecyl glycol copolymer, andmixtures thereof.

Another particular suitable class of O/W emulsifiers are non-ionicself-emulsifying system derived from olive oil e.g. known as (INCI Name)cetearyl olivate and sorbitan olivate (Chemical Composition: sorbitanester and cetearyl ester of olive oil fatty acids) sold under thetradename OLIVEM 1000.

Further suitable are commercially available polymeric emulsifiers suchas hydrophobically modified polyacrylic acid such as Acrylates/C10-30Alkyl Acrylate Crosspolymers which are commercially available under thetradename Pemulen® TR-1 and TR-2 by Noveon.

Another class of particularly suitable emulsifiers are polyglycerolesters or diesters of fatty acids also called polyglyceryl ester/diester(i.e. a polymer in which fatty acid(s) is/are bound by esterificationwith polyglycerine), such as e.g. commercially available at Evonik asIsolan GPS [INCI Name Polyglyceryl-4Diisostearate/Polyhydroxystearate/Sebacate (i.e. diester of a mixture ofisostearic, polyhydroxystearic and sebacic acids with Polyglycerin-4)]or Dehymuls PGPH available at Cognis (INCI Polyglyceryl-2Dipolyhydroxystearate).

Also suitable are polyalkylenglycolether such as Brij 72(Polyoxyethylen-(2)stearylether) or Brij 721 (Polyoxyethylene (21)Stearyl Ether e.g. available at Croda.

The at least one O/W respectively Si/W emulsifier is preferably used inan amount of 0.5 to 10 wt. % such as in particular in the range of 0.5to 5 wt.-% such as most in particular in the range of 0.5 to 4 wt.-%based on the total weight of the composition.

Suitable W/O- or W/Si-emulsifiers arepolyglyceryl-2-dipolyhydroxystearat, PEG-30 dipolyhydroxystearat, cetyldimethicone copolyol, polyglyceryl-3 diiso-polyglycerol esters ofoleic/isostearic acid, polyglyceryl-6 hexaricinolate,polyglyceryl-4-oleate, polygylceryl-4 oleate/PEG-8 propylene glycolcocoate, magnesium stearate, sodium stearate, potassium laurate,potassium ricinoleate, sodium cocoate, sodium tallowate, potassiumcastorate, sodium oleate, and mixtures thereof. Further suitableW/Si-emulsifiers are Lauryl Polyglyceryl-3 PolydimethylsiloxyethylDimethicone and/or PEG-9 Polydimethylsiloxyethyl Dimethicone and/orCetyl PEG/PPG-10/1 Dimethicone and/or PEG-12 Dimethicone Crosspolymerand/or PEG/PPG-18/18 Dimethicone. The at least one W/O emulsifier ispreferably used in an amount of about 0.001 to 10 wt.-%, more preferablyin an amount of 0.2 to 7 wt.-% with respect to the total weigh of thecomposition.

The cosmetic compositions according preferably furthermoreadvantageously contain at least one co-surfactant such as e.g. selectedfrom the group of mono- and diglycerides and/or fatty alcohols. Theco-surfactant is generally used in an amount selected in the range of0.1 to 10 wt.-%, such as in particular in the range of 0.5 to 6 wt.-%,such as most in particular in the range of 1 to 5 wt.-%, based on thetotal weight of the composition. Particular suitable co-surfactants areselected from the list of alkyl alcohols such as cetyl alcohol (LorolC16, Lanette 16), cetearyl alcohol (Lanette 0), stearyl alcohol (Lanette18), behenyl alcohol (Lanette 22), glyceryl stearate, glyceryl myristate(Estol 3650), hydrogenated coco-glycerides (Lipocire Na10) as well asmixtures thereof.

The amount of emulsifier is preferably in the range between 0.1-6.0% byweight, more preferably between 0.25-5.0% by weight, particularlybetween 0.5-4.0% by weight, based on the total weight of the cosmeticcomposition.

The composition is preferably sulfate-free.

Hence, the cosmetic composition is preferably particularly free ofsulfates of the group consisting of alkyl sulfates, alkyl ethersulfates, alkyl amido ether sulfates, alkylaryl polyether sulfates andmonoglycerides sulfate as well as mixtures thereof.

The term “free” as used in the present document, for example in“sulfate-free”, is used to mean that the respective substance is onlypresent at amounts of less than 0.5% by weight, particularly less than0.1% by weight, more particularly below 0.05% by weight, relative to theweight of the composition. Preferably, “free” means that the respectivesubstance is completely absent in the composition.

The term “sulfate-free” is used in the present document to mean that thecomposition is free of any anionic tenside having a terminal anionicgroup of the formula

The cosmetic composition is preferably free of cationic emulsifiers.Typical example for such cationic emulsifiers are isostearamidopropyldimethylamine, stearalkonium chloride, stearamidoethyl diethylamine,behentrimonium methosulfate, behenoyl PG-trimonium chloride, cetrimoniumbromide, behenamidopropyl dimethylamine behenate, brassicamidopropyldimethylamine, stearamidopropyl dimethylamine stearate, cocamidopropylPG-dimonium chloride, distearoylethyl hydroxyethylmonium methosulfate,dicocoylethyl hydroxyethylmonium methosulfate, distearoylethyl dimoniumchloride, shea butteramidopropyltrimonium chloride, behenamidopropyldimethylamine, brassicyl isoleucinate esylate, acrylamidopropyltrimoniumchloride/acrylates copolymer, linoleamidopropyl ethyldimoniumethosulfate, dimethyl lauramine isostearate, isostearamidopropyllaurylacetodimonium chloride, particularly behentrimonium chloride,distearyldimonium chloride, cetrimonium chloride, steartrimoniumchloride, and palm itamido-propyltrimonium chloride.

The composition may comprise preferably a further UV filter. The furtherUV filter may be solid or liquid. It is preferred that the further UVfilter is a solid UV filter.

Suitable liquid organic UV-filter absorb light in the UV(B) and/or UV(A)range and are liquid at ambient temperature (i.e. 25° C.). Such liquidUV-filter are well known to a person in the art and encompass inparticular cinnamates such as e.g. octyl methoxycinnamate (PARSOL® MCX)and isoamyl methoxycinnamate (Neo Heliopan® E 1000), salicylates such ase.g. homosalate (3,3,5 trimethyl-cyclohexyl 2-hydroxybenzoate, PARSOL®HMS) and ethylhexyl salicylate (also known as ethylhexyl salicylate,2-ethylhexyl 2-hydroxybenzoate, PARSOL® EHS), acrylates such as e.g.octocrylene (2-ethylhexyl-2-cyano-3,3-diphenylacrylate, PARSOL® 340) andethyl 2-cyano-3,3 diphenylacrylate, esters of benzalmalonic acid such asin particular dialkyl benzalmalonates such as e.g. di (2-ethylhexyl)4-methoxybenzalmalonate and polysilicone 15 (PARSOL® SLX), dialkylesterof naphthalates such as e.g. diethylhexyl 2,6-naphthalate (Corapan® TQ),syringylidene malonates such as e.g. diethylhexyl syringylidene malonate(Oxynex® ST liquid) as well as benzotriazolyl dodecyl p-cresol(Tinoguard® TL) as well as benzophenone-3 and drometrizole trisiloxane.

Particular advantageous liquid organic UV-filter are octylmethoxycinnamate, homosalate, ethylhexyl salicylate, octocrylene,diethylhexyl 2,6-naphthalate, diethylhexyl syringylidene malonate,benzotriazolyl dodecyl p-cresol, benzo-phenone-3, drometrizoletrisiloxane as well as mixtures thereof.

In a preferred embodiment, the liquid UV filter is a liquid UV(B) filterwhich is selected from the group consisting of ethylhexylmethoxycinnamate, octocrylene, homosalate, ethylhexyl salicylate,benzophenone-3 and drometrizole trisiloxane.

Suitable solid organic UV-filter absorb light in the UV(B) and/or UV(A)range and are solid at ambient temperature (i.e. 25° C.). Particularlysuited solid UV-filters are of the group consisting ofbis-ethylhexyloxyphenol methoxyphenyl triazine, butyl methoxydibenzoylmethane, methylene bis-benzotriazolyl tetramethylbutylphenol,diethylamino hydroxybenzoyl hexyl benzoate, ethylhexyl triazone,4-methylbenzylidene camphor and 1,4-di(benzoxazol-2′-yl)benzene.

A preferred solid organic UV(A) filter is a UV(A) filter which isselected from the group consisting of bis-ethylhexyloxyphenolmethoxyphenyl triazine, butyl methoxydibenzoyl methane, methylenebis-benzotriazolyl tetramethylbutylphenol, diethylamino hydroxybenzoylhexyl benzoate and tris-biphenyl triazine.

A preferred solid organic UV(B) filter is a UV(B) filter which isselected from the group consisting of ethylhexyl triazone (=Uvinul®T150), and 4-methylbenzylidene camphor (=PARSOL® 5000).

The total amount of organic UV filter (s) depends strongly on thetargeted UV protection.

It is preferred that the amount of a solid organic UV filter, particularof solid organic UV(A) filter, is selected in the range of 0.1 to about6 wt.-%, preferable in the range of 0.5 to 5 wt.-%, most preferably inthe range of 1 to 4 wt.-%.

It is further preferred that amount of a solid organic UV filter,particular of solid organic UV(B) filter, is selected in the range of0.1 to about 6 wt.-%, preferable in the range of 0.5 to 5 wt.-%, mostpreferably in the range of 1 to 4 wt.-%.

It is even further preferred that amount of a liquid organic UV filter,particular of liquid organic UV(B) filter, is selected in the range of0.1 to about 10 wt.-%, preferable in the range of 0.5 to 12 wt.-%, mostpreferably in the range of 1 to 10 wt.-%.

The cosmetic composition further may comprise cosmetic carriers,excipients and diluents as well as additives and active ingredientscommonly used in the skin care industry which are suitable for use inthe cosmetic compositions are for example described in the InternationalCosmetic Ingredient Dictionary & Handbook by Personal Care ProductCouncil (http://www.personalcarecouncil.org/), accessible by the onlineINFO BASE (http://online.personalcarecouncil.org/jsp/Home.jsp), withoutbeing limited thereto.

Such possible ingredients of the cosmetic composition are particularlyenhance the performance and/or consumer acceptability such aspreservatives, antioxidants, fatty substances/oils, thickeners,softeners, light-screening agents, moisturizers, fragrances,co-surfactants, fillers, sequestering agents, cationic-, nonionic- oramphoteric polymers or mixtures thereof, acidifying or basifying agents,viscosity modifiers, and natural hair nutrients such as botanicals,fruit extracts, sugar derivatives and/or amino acids or any otheringredients usually formulated into cosmetic compositions. The necessaryamounts of the adjuvants and additives can, based on the desiredproduct, easily be chosen by a person skilled in the art in this fieldand will be illustrated in the examples, without being limited hereto.

Particularly suitable thickeners in all embodiments are xanthan gum,gellan gum and/or carboxymethylcellulose. Most preferably in allembodiments the thickener is xanthan gum or gellan gum.

Such thickener(s) are preferably used in an amount (total) selected inthe range from 0.1 to 1 wt.-%, more preferably in an amount of 0.1 to0.5 wt.-%, based on the total weight of the cosmetic composition.

The cosmetic compositions have preferably a pH in the range from 3 to10, preferably a pH in the range from 4 to 8 and most preferably a pH inthe range from 4 to 7.5. The pH can easily be adjusted as desired withsuitable acids such as e.g. citric acid or bases such as NaOH accordingto standard methods in the art.

The cosmetic composition is preferably sulfate-free and/or free ofpara-bens, and/or silicone oils and/or silicone surfactants.

The cosmetic composition is preferably a topical composition.

The term “topical” as used herein is understood here to mean externalapplication to keratinous substances, which are in particular the skin,scalp, eyelashes, eyebrows, nails, mucous membranes and hair, preferablythe skin.

As the topical compositions are intended for topical application, it iswell understood that they comprise a physiologically acceptable medium,i.e. a medium compatible with keratinous substances, such as the skin,mucous membranes, and keratinous fibers. In particular, thephysiologically acceptable medium is a cosmetically acceptable carrier.

The term “cosmetically acceptable carrier” refers to all carriers and/orexcipients and/or diluents conventionally used in cosmetic compositionssuch as in particular in sun care products.

Preferably the cosmetic composition is a skin care preparation,decorative preparation, or a functional preparation.

Examples of skin care preparations are, in particular, light protectivepreparations, anti-ageing preparations, preparations for the treatmentof photo-ageing, body oils, body lotions, body gels, treatment creams,skin protection ointments, skin powders, moisturizing gels, moisturizingsprays, face and/or body moisturizers, skin-tanning preparations (i.e.compositions for the artificial/sunless tanning and/or browning of humanskin), for example self-tanning creams as well as skin lighteningpreparations.

Examples of functional preparations are cosmetic or pharmaceuticalcompositions containing active ingredients such as hormone preparations,vitamin preparations, vegetable extract preparations and/or anti-ageingpreparations without being limited thereto.

The cosmetic composition is preferably a skin care composition.

In a most preferred embodiment, the cosmetic composition is a sun carecomposition. Sun care compositions are light-protective preparations(sun care products), such as sun protection milks, sun protectionlotions, sun protection creams, sun protection oils, sun blocks or daycare creams with a SPF (sun protection factor). Of particular interestare sun protection creams, sun protection lotions, sun protection milksand sun protection preparations.

The cosmetic compositions have improved sensory properties, particularimproved afterfeel, and are capable to have a higher amount of UV-filterof the formula (I) been solubilized as compared with the respectivecosmetic compositions being devoid of said ester of a fatty acid anddextrin and devoid of mixture of branched and linear saturated C15-C19alkanes and particularly devoid of any silicone oil.

It has been observed that UV filter of formula (I) can be bettersolubilized in liquid saturated C8-C30 alkanes by adding an ester of afatty acid and dextrin.

As both ingredients are available from biological origin, it is possibleto obtain this improvement in a sustainable way which is a big advantageof the present invention.

Hence, in a further aspect, the present invention relates to the use ofadding an ester of a fatty acid and dextrin to increase thesolubilization of solid organic UV filters in liquid saturated C8-C30alkanes, particularly in branched and linear saturated C15-C19 alkanes.

The liquid saturated C8-C30 alkanes are particularly selected from thegroup consisting of C8-C30 mineral oils, decane, undecane, dodecane,hexadecane, octadecane, squalene(=2,6,10,15,19,23-hexamethyltetracosane), farnesane(=2,6,10-trimethyldodecane), dodecane, isopentadecane, isohexadecane,isooctadecane, isononadecane, and the branched and linear saturatedC15-C19 alkanes, particularly the in branched and linear saturatedC15-C19 alkanes as discussed above in great details.

It has been observed that the UV filter of formula (I) can be bettersolubilized in a cosmetic composition by combining the UV filter offormula (I) with particularly an ester of a fatty acid and dextrin and amixture of branched and linear saturated C15-C19 alkanes.

Hence, in a further aspect, the present invention relates to a method ofincreasing the solubilization of a UV filter of formula (I) in acosmetic composition by combining the UV filter of formula (I)

with an ester of a fatty acid and dextrin and a mixture of branched andlinear saturated C15-C19 alkanes.

Examples

The present invention is further illustrated by the followingexperiments.

Cosmetic Compositions and Solubilisation of Iscotrizinol Preparation ofa Premix

In examples 1 and 2, the dextrin palmitate has been premixed with a partof the C15-C19 alkane to form a pre-mix (Dextrin palmitate 25% byweight).

Said premix has then mixed with the UV filter and the rest of the C15-19alkane by a magnetic stirrer at 80 C, let cool down without any stirringto 25° C. After one week storage of the solution at 25° C. a sample hasbeen taken with a pipette from the bottom of the flask and observedunder the microscope (Microscope Zeiss AX-under polarizer light,magnification ×100, camera Deltapix Invenio 5D). The microscopicpictures are shown in the FIGS. 1 to 4 .

The viscosities have been measured on a Rheometer AR550 from TAInstruments using a 40 mm plate and a shear 10/s at 25° C.

TABLE 1 Cosmetic compositions comprising Iscotrizinol (all ingredientsin % by weight). Ref. 1 1 2 Ref. 2 UVASORB ® HEB [%]¹    2    2    2   2 C15-19 alkane [%]²   98    88   88   88 Dextrin Palmitate 1 [%]³   10 Dextrin Palmitate 2 [%]⁴   10 Oilkemia 5S [%]⁵   10 Aspect ClearWhite gel White gel No gel with with very with very with many many fewfew crystals and crystals crystals crystals agglomerate Viscosity [mPa ·s] <10 37'460 3'023 <10 Microscope picture FIG. 1 FIG. 3 FIG. 4 FIG. 2¹Iscotrizinol ²EMOGREEN ™ L19 ³Rheopearl ® KL2, Chiba Flour MillingDextrin Palmitate: M_(n) = 11'300-11'500 Da, determined by SEC/GPC⁵Polyurethane polymer (INCI Polyuethane-79) (30% in Caprylic/Caprictriglycerides), Lubrizol

It has been shown, that the UV filter was not been able to solubilize inC15-19 alone (Ref.1) or in a polyurethane-based thickener (Ref.2). Inboth cases significant amounts of crystals (and agglomerates in Ref.2)of the UV filter have been found at the bottom off the flask (see FIG.1, 2 ). In both cases, no gel was formed and the viscosity of thecomposition was very low (<10 mPas).

In case of the examples 1 and 2 the UV filter was excellentlysolubilized and only a few crystals (see FIGS. 3 and 4 ), have beenobserved. Example 2 showed less crystals than example 1. In both cases,a gel has formed and a viscosity of more than 2000 mPas has beenobserved.

1. A composition comprising an ester of a fatty acid and dextrin a mixture of branched and linear saturated C15-C19 alkanes a UV-filter of the formula (I)

wherein the amount of branched saturated C15-C19 alkane in said mixture of branched and linear saturated C15-C19 alkanes is more than 80% by weight, preferably more that 90% by weight, most preferred more than 92% by weight.
 2. The composition according to claim 1, wherein the amount of linear saturated C15-C19 alkanes in said mixture of branched and linear saturated C15-C19 alkanes is less than 10% by weight, preferably less than 8% by weight, most preferred more than 5% by weight.
 3. The composition according to claim 1, wherein amount of branched saturated C18 alkane is more than 50% by weight, preferably more than 60% by weight, even more preferably more than 70% by weight, relative to the weight of said mixture of branched and linear saturated C15-C19 alkanes.
 4. The composition according to claim 1, wherein the fatty acid of said ester of a fatty acid and dextrin is a C14-C18 fatty acid, particularly a linear C14-C18 fatty acid, most preferably palmitic acid.
 5. The composition according to claim 1, wherein the dextrin of said ester of a fatty acid and dextrin has an average degree of glycopolymerization of between 3 and 20, particularly between 8 and
 16. 6. The composition according to claim 1, wherein said ester of a fatty acid and dextrin has an average number of esterified hydroxyl groups of more than 3, preferably between 3.05 and 3.5, more preferably between 3.1 and 3.4, most preferably between 3.1 and 3.2 per glucose unit.
 7. The composition according to claim 1, wherein said ester of a fatty acid and dextrin has an molecular weight M_(n) of between 8,000 and 16,000 Da, preferably between 9,000 and 13,000 Da, more preferably between 10,000 and 11′500 Da.
 8. The composition according to claim 1, wherein the ratio of the weight of said ester of a fatty acid and dextrin to the weight of said mixture of branched and linear saturated C15-C19 alkanes is less than 100% by weight, preferably in the range of 50-80% by weight, most preferred in the range of 60-70% by weight.
 9. The composition according to claim 1, wherein the weight ratio of the UV-filter of the formula (I) to the ester of a fatty acid and dextrin is 100:1 to 1:100, preferably 80:1 to 1:100, more preferably 70:1 to 1:20, most preferably 60:1 to 1:10.
 10. The composition according to claim 1, wherein the composition comprises water and is in the form of an emulsion.
 11. The composition according to claim 1, wherein the composition is in the form of a gel.
 12. The composition according to claim 1, wherein the composition has a Sun Protection Factor (SPF) of 10 or higher, preferably of 20 or higher, more preferred of 30 or higher, even more preferred 50 or higher.
 13. Use of adding an ester of a fatty acid and dextrin to increase the solubilization of solid organic UV filters in liquid saturated C8-C30 alkanes, particularly in branched and linear saturated C15-C19 alkanes.
 14. A method of increasing the solubilization of a UV filter of formula (I) in a cosmetic composition by combining the UV filter of formula (I)

with an ester of a fatty acid and dextrin and a mixture of branched and linear saturated C15-C19 alkanes. 